Shurima Ascension Rewards

I've looked for information regarding how to claim the rewards of played 'Ascension' games, but have been unable to find anything related in topic other than how to get them via the promo link I've included in this post. Are the rewards not available for this game mode? If so, how or when do they become available for players to collect? Any information regarding the "Claim Rewards" section of the Shurima promotional page is appreciated. Thank you.